Piston ring



"Nov. 5, 1929. D. M. SOLENBERGER 1,734,055

PISTON RING Filed Sept. 26, 1927 511mm ufo@ eaf? 502672567 (fr Fatented Nov. 5,!1929' UNITED STATES PATENT OFFICE DEAN MJSOLENBRGER, OF CLEVELAND, OHIO, ASSIGNOR T THE SIMPLEX PISTON RING COMPANY'OF AMERICA, INC., .A CORPORATION 0F OHIO PISTON RING Application led September 26, 1927. -Serial No. 222,092.

The invention relates topiston rings'of that type circumferentially slotted for axial resiliency and the invention consists in the v Figure l isa section through a portion of thepiston -provided with three ring grooves showing my improved construction-of ring in the lower groove. Figure 2 is a side elevation of a portion of the-ring;

Figure 3 is a cross section thereof. igure 4 is a view similar to Figure 2 showing a modification.

In /the manufacture of circumferentially slotted rings it is usual to form the slots as narrow as possible. It is of course, necessary that the slotting saws should be of sucient gauge or strength to performthe work and it is also necessary to remove' sufficient material for the axial contraction of the ring through which the axially expansible tension is developed. However, both of these effects may be produced by the use of comparatively narrow gauge saws.

It is the primary object of the present invention to obtain a ring which will have increased efficiency in barring the passage of oil or, what is lcommonly known as oil.. pumping. This I have accomplished by increasing the width of the slots'so as to first reduce the peripheral contact area of the ring and second, provide wider passages for the oil,

through the ring into the grove.

As shown A is the piston having three ring groox` es therein, B, B B the groove B2 being provided with drain apertures C through the piston wall. D is anl ordinary solid section ring occupying the upper grove B. E is a circumferentially slotted and axially resilient ring occupying the second groove with a corrugated ribbon expander F for assisting in radial expansion and G a ring of my improved construction occupying the grove B2. As clearly shown in Figure 1 one of the slots in the ring .G is much greater in Width than the slots in the ring E and consequently the area of peripheral contact may be determined by specilic conditions and is entirely independent slot G3.

termined not only by the width of the portion of the factorof axial tension.. This is for the reason thatthe axial tension is produced by rthe deflection only ofthat portion Gvof thering between the upper slots G2 and the. i

lowerslots-Gf and is not materially affected by theQwidth of the portions Gi* and G5 respectively above the'slot G2 and' below the Furthermore the axial tension is de- G but also by itslength between the unslotted portions G6 andGr7 vat opposite ends thereof, tension` and the respective open and closed peripheral areas may be independently chosen.A v f l It is very important-in designing a slotted ring to guard against the possibility of bending'any portion thereof beyond. the elastic limitV which would result in breakage'. With the construction of the ring E which has comparatively narrow slots the amount of flexing permited to the intermediate bars remains within safe limits but with wide slots as indicated at G2 there would be danger. I have, however, avoided this difficulty by making the lower slots Ga narrow so that axial Thus in designing'the rin'gaxial upper portion reduced in radial depth while its lower portion is provided with 'an inwardly extending flange H5 to increasethe land contact onthe lower -face of the ring groove.

The ring is also provided with a corrugated ribbon expander J of a width less than that of the ring andv held from displacement by the flange H5. This construction is particularly useful in connection with the cylinders which are distorted or non-circular as the increased flexibility of the ring together with the dis'- tributed radial pressure of the expander permits of conforming to such distortions. the other hand for many purposes the ring may be constructed as showin in Figure 3 Where it is of full radial depth and depends uponits own resiliency for radial ex ansion.

In operation the ring in siding over the oiled surface of the cylinder wall -Will permit the passage of oil inward through the slots while the restricted area of peripheral contact under the radial expansive pressure tends to thin the oil film and to preventits passage into the combustion chamber. The upper and lower slots being staggered in relation to each other provides all ortions of the ring with at least one slot there y avoiding leakage of the lubricant by the ring at any point.

What I claim as my invention is:

1. A piston ring slotted for axial resiliency and for the passage of lubricant inward therethrough the Width of some of said slots being greater than the permissible axial contracttion of ther-ing and means for preventing collapsing ofthe ring beyond said permissible limit.

2. A piston ring of a normal width greater than the ring groove circumferentially slotted for axial resiliency and for the passage of lubricant therethrough, said slots beingxarranged in staggered series to produce flexible bars therebetween, the slots of one series being limited in Width to limit the flexing of sald bars and the slots of the other series being of greater width to increase the oil passage and to diminish the area of peripheral contact.

In testimon whereof I aiiix my signature.

DAN M. SOLENBERGER. 

